The present invention relates to a device for the testing and quantifying of suspension shock absorbers, specifically as fitted to the suspension systems of vehicles. In particular, the present invention is related to a shock absorber dynamometer.
In the past, shock absorber dynamometers took the form of electrically, pneumatically or hydraulically driven apparatus. In operation, the dynamometers tested a fitted suspension shock absorber by actuating the fitted shock absorber with a complex electrical, pneumatic, or hydraulic drive system. The dynamometers often provided numerical or graphical data for comparison and relation of modifications and adjustments to the dampening characteristics of the fitted shock absorber to modified versions of itself and to other shock absorbers. However, shock absorber dynamometers were large and complex because they were used to test large or full-scale suspension shock absorbers as fitted to large or full-scale vehicles.
Part of the complexity in past dynamometers arose, in part, due to their drive systems. In particular, the drive systems required external power sources and complex control systems to maintain reliable speed and/or force of actuation. Thus, prior dynamometers were comparatively large due to the requirements of these drive systems and relatively expensive due to the components necessary for accurate and reliable actuation and measurement.
The present shock dynamometer provides a convenient, reliable, compact and relatively inexpensive device to test and quantify small and scale suspension shock absorbers as used on small and scale vehicles.
The dynamometer includes a drive system that is actuated by the energy of a falling weight of predetermined mass. This weight is attached to a cable of predetermined length wound around a spool of predetermined diameter that rotates a shaft onto which a crank is fixed. The shock absorber is fitted to the crank and the upper end of the shock absorber is fixed to a tower. When the weight is released, the crank actuates the shock absorber through a predetermined number of rotations or cycles. One rotation or cycle of the crank comprises one compression stroke and one extension stroke of the fitted shock absorber. A trigger mounted to the drive shaft of the unit allows a timing device to compute and display the dampening effect of the fitted shock absorber upon the fall of the weight.
A drive comprising a falling weight is convenient and reliable because no external power sources or complex control systems are required. Furthermore, the reliability and consistency of the drive speed and force are only effected by the small fluctuations in the force of Earth""s gravity. The reduced complexity of the drive system and of the timing and display unit allow the dynamometer to be manufactured relatively inexpensively and easily sized for its intended use.